Network Video Record (NVR) systems are being widely used for the purposes of crime prevention, traffic control, information collection, etc. Such an NVR system is connected to a plurality of image input devices over a network, and is operated at all times.
Accordingly, although it is essential that a NVR system should be stably operated over a long time and should be normally operated without requiring additional manpower, a failure may occur in a network connection with an image input device because of the disconnection of a cable or the overload of a network.
Conventional technology has a problem determining a network connection failure between a server and an image input device in that the connection failure should be determined by manual operation or irregular determination, such as the determination of logs that have not been stored.
That is, the conventional technology NVR systems are problematic in that they cannot easily determine a connection failure that occurs when an image is received from an individual image input device, such that it takes a long time to determine a connection failure attributable to the disconnection of a cable or the overload of a network and it is ineffective to perform irregular human monitoring.